Effect of Entonox on Pain Relief and Duration of Labour in Nulliparous Patients Presenting for Delivery at Term

Abstract

Objective: To investigate the effect of Entonox on labor pain and labour duration in primiparous women.

Methodology: This randomized controlled trial was conducted at the Department of Obstetrics and Gynaecology, Shifa, International Hospital, Islamabad, over a six months period from 01-09-2021 to 28-02-2022 after approval by Institutional Etics Committee. Study population were nulliparous ladies, aged 18-40 years, presenting in active labourat gestational age. ≥ 37 weeks with any of these comorbid conditions: well controlled preexisting or gestational diabetes (deranged OGTT), non proteinuric, well controlled hypertension, (BP≥140/90), anemia (Hb<8g/dl) and morbid obesity, A total of 60 patients (30 in each group) were included the study. Group-A received Entonox while Group-B was administered with placebo.Mean pain score of first and second stage of labour was noted using VAS ,duration of first and second stahe of labours was recorded. Side effects were recorded Data was entered and data analysed using SPSS version 21.

Results: Both groups were comparable in terms of age, gestational age and BMI. Entonox inhalation resulted in shorter labour duatrion amd lower pain score. Mean duration of first stage of labour, in group-A it was 3.73±0.45 and in group-B was 5.64±0.88 hours (p. <0.001). Similarly mean duration of 2nd stage of labour was 1.288±0.48 hours in group-A and 1.93± 0.87 hours in in group-B (p <0.001). In group-A pain score in 1st stage of labour was 3.07±1.06 and in group-B it was 7.20±0.66 (p<0.001) while in 2nd stage of labour in group-A mean pain score was seen 4.23±1.04 and in group-B 8.81 3±0.50(p<0.001)

Conclusion: Entonox consumption showed pain relief in women during first and second stage of labour and a decrease in the length of their labour. No significant reported complication of Entonox was an advantage of this analgesic method. Therefore, to decrease labour pain, Entonox inhalation analgesia is useful.